Previously, it was thought that the tropes of being a teenager ended in your teen years — aka at 19 — however societal and lifestyle changes have made this a thing of the past.

The report argues that the extension of adolescence is down to young people delaying many of the traditional markers of adulthood — things like getting married, having children and buying your own home.

This delay is thanks to a mix of cultural and economic changes — many people don't want to get married or have children at all, while others are putting off these decisions to focus on their career, or because of financial insecurity.

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